Void cells with outwardly curved surfaces

ABSTRACT

Implementations described and claimed herein include a cushioning structure and method for manufacturing a cellular cushioning system, which allows for maximum comfort through the compression and shock cycle. Specifically, a cushioning structure comprises void cells formed in an array, which comprise multiple outwardly curved surfaces, with varying radius measurements. Stiffness in the void cells can vary by varying the radii. The outwardly curved surfaces prevent buckling and provide support for high impact by absorbing energy.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of U.S.Non-Provisional patent application Ser. No. 15/748,702, entitled “VOIDCELLS WITH OUTWARD FACING CURVATURE,” filed on Jan. 30, 2018, which is aUS national entry from international patent application No.PCT/US2016/045049, entitled “VOID CELLS WITH OUTWARD FACING CURVATURE,”filed on Aug. 1, 2016, both of which are specifically incorporated byreference for all it discloses and teaches.

The present application further claims priority to U.S. ProvisionalPatent Application Ser. No. 62/199,810, entitled “VOID CELLS WITHOUTWARD FACING CURVATURE,” filed on Jul. 31, 2015, and to U.S.Provisional Patent Application Ser. No. 62/219,451, entitled “VOID CELLSWITH OUTWARD FACING CURVATURE,” filed on Sep. 16, 2015, both of which isspecifically incorporated by reference for all they disclose and teach.

BACKGROUND

Cushioning systems are used in a wide variety of applications includingcomfort and impact protection of the human body. A cushioning system isplaced adjacent a portion of the body and provides a barrier between thebody and one or more objects that would otherwise impinge on the body.For example, a pocketed spring mattress contains an array ofclose-coupled metal springs that cushion the body from a bed frame.Similarly, footwear, chairs, gloves, knee-pads, helmets, etc. may eachinclude a cushioning system that provides a barrier between a portion ofthe body and one or more objects.

A variety of structures are used for cushioning systems. For example, anarray of close-coupled, closed-cell air and/or water chambers oftenconstitutes air and water mattresses. An array of close-coupled springsoften constitutes a conventional mattress. Further examples include openor closed cell foam and elastomeric honeycomb structures.

For cushioning systems utilizing an array of closed or open cells orsprings, either the cells or springs are directly coupled together orone or more unifying layers are used to couple each of the cells orsprings together at their extremities. Directly coupling the cells orsprings together or indirectly coupling the extremities of the cells orsprings together is effective in tying the cushioning system together.

SUMMARY

Implementations described and claimed herein include a cushioningstructure and method for manufacturing a cellular cushioning system,which allows for maximum comfort through the compression and shockcycle. Specifically, a cushioning structure comprises mutated void cellsformed in an array, which comprise of multiple outwardly curved surfacesof varying radius measurements. Stiffness in the void cells can bemanipulated by varying the radii. The outwardly curved surfaces preventbuckling and provide support for high impact by absorbing energy.

Other implementations are also described and recited herein.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 2A illustrates a top view of an example base portion of a void cellin one array of the example cellular cushioning system.

FIG. 2B illustrates a top view of an example base portion of a void cellin one array of the example cellular cushioning system.

FIG. 3 illustrates a top view of the example cellular cushioning systemin FIG. 1.

FIG. 4 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 5 illustrates a top view of the example cellular cushioning systemin FIG. 4.

FIG. 6 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 7 illustrates a top view of the example cellular cushioning systemin FIG. 6.

FIG. 8 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 9 illustrates a top view of the example cellular cushioning systemin FIG. 8.

FIG. 10 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 11 illustrates a top view of the example cellular cushioning systemin FIG. 10.

FIG. 12 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 13 illustrates an elevation view of the example cellular cushioningsystem in FIG. 12.

FIG. 14 illustrates a top view of the example cellular cushioning systemin FIG. 12.

FIG. 15 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 16 illustrates an elevation view of the example cellular cushioningsystem in FIG. 15.

FIG. 17 illustrates a top view of the example cellular cushioning systemin FIG. 15.

FIG. 18 illustrates a perspective view of an example cellular cushioningsystem in an unloaded state.

FIG. 19 illustrates an elevation view of the example cellular cushioningsystem in FIG. 18.

FIG. 20 illustrates a top view of the example cellular cushioning systemin FIG. 18.

FIG. 21 shows a graph of force displacement of void cells in arrays ofthe described cushioning systems.

FIG. 22 shows a table of load force based on 10%, 25%, 50%, and 75%compression for the void cells in arrays of the described cushioningsystems.

FIG. 23 illustrates example operations of manufacturing an examplecellular cushioning system.

DETAILED DESCRIPTIONS

The disclosed technology includes a cushioning structure, which allowsfor maximum comfort through the compression and shock cycle.Specifically, a cushioning structure comprises of mutated void cellsformed in an array or a sheet, which comprise of multiple outwardlycurved surfaces, with varying radius measurements. The elastic modulusor stiffness in the void cells can be manipulated by varying the number,the depths, and the locations (e.g., vertical height) of the radii inthe void cells. The outwardly curved surfaces dominate the overalldesign of the void cell and prevent buckling and provide support forhigh impact by absorbing energy. The void cells in the disclosedtechnology can withstand over multiple compressions without significantdegradation.

Void cells without outwardly curved surfaces can experience buckling andloss of support in void cells during impact. The void cells withoutoutwardly curved surfaces can displace too rapidly and not absorb asmuch energy. Therefore, it is beneficial to have a configuration thatdoes not endure stress concentrations within the material itself (e.g.,folds that might create a crack over time or create a significantdecrease in force deflection performance over time).

The disclosed technology can be used in a variety ofcomfort-impact-protection and pressure-distribution cushioningapplications, including, but not limited to: footwear, mattresses,furniture cushioning, body padding, and packaging. In oneimplementation, the void cells comprising multiple outwardly curvedsurfaces can support footwear capable of withstanding threes times auser's body weight during use.

FIG. 1 illustrates a perspective view of an example cellular cushioningsystem 100 in an unloaded state. The cellular cushioning system 100includes void cells (e.g., void cell 102 or void cell 104) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells. The arrays can be flat or curved.

For purposes of this disclosure, the arrays in example cellularcushioning systems 100 that include two arrays are described as a firstarray (e.g., first array 106) and a second array (e.g., second array108). However, in another implementation, the first array and secondarray could be referred to as right side and left side arrays, top andbottom arrays, or other named features depending on desired terminologyor configurations. In implementations with more than one array in thecellular cushioning system 100, the void cells 104 in each array mayhave the same or different geometries as another array. Additionally,the void cells 104 within a single array can have the same or differentgeometries from each other.

In FIG. 1, the first array 106 and the second array 108 have void cells(e.g., void cell 104), which comprise of four outwardly curved surfaces(e.g., outwardly curved surfaces 110), each outwardly curved surface ineach sidewall (e.g., sidewall 120) of each void cell 104) in the firstarray 106 and the second array 108 in the cellular cushioning system100. The outwardly curved surfaces are located on the sidewalls of thevoid cells and are curvatures facing naturally away from the interior ofthe void cell. The outwardly curved surfaces constitute a substantialportion of the overall exterior surface area of the void cell 104,defined as greater than or equal to 20% of the overall exterior surfacearea of the void cell 104.

Each void cell 104 also comprises of four inwardly curved surfaces(e.g., inwardly curved surfaces 126), wherein one inwardly curvedsurface constitutes a rounded corner of the void cell 100. In FIG. 1,the inwardly curved surfaces are located on the corners of the voidcells and are curvatures facing inwardly toward the interior of the voidcells.

In implementations of the disclosed technology, the outwardly curvedsurfaces and inwardly curved surfaces can be configured in a sidewall ofa void cell or on a corner of a void cell. In some implementations,there can be two, three, or more curved surfaces (or interchangeablyreferred herein as curvatures) in each void cell. In someimplementations, there may be more than one curvature in a sidewall of avoid cell. For example, there may be a wave of curvatures in thesidewalls (e.g., about 12 oscillations yielding a very stiff cell). Inother implementations, there may be no curvatures in one or moresidewalls.

In some implementations, a cubic shape of a base portion (e.g., baseportion 130) of a void cell can adopt the slope of its cubic shape of anadjacent or adjoined void cell (e.g., void cell 104). The base portion130 can be defined as a portion of the void cell adjacent to a peakportion (peak portion 132), which forms at least a medial portion of avoid cell. The peak portion 132 may be defined as a portion of the voidcell adjacent to a base portion 130, which includes a peak surface(e.g., peak surface 112) that may attach to a peak surface of anopposing void cell in another array (not shown) of the void cell (e.g.,void cell 104). The peak portion 132 may be significantly rounded orsegmented as a result of a larger radius or of a deeper depth of eachoutwardly curved surface (e.g., outwardly curved surface 110), or by thenumber of outwardly curved surfaces present in each void cell. A largerradius of the outwardly curved surfaces may be approximately 50% of thelength of the void cell or less. In one example, the larger radius ofthe outwardly curved surfaces may be approximately 20 mm. In anotherexample, a larger radius may be half the length of the void cell 104less 1 mm. (The radii and depths of the outwardly curved surfaces aredescribed in detail in FIG. 2.)

In some implementations, the base portion 130 includes only the inwardlycurved surfaces and a peak portion 112 that includes both the outwardlycurved surfaces 110 and the inwardly curved surfaces 126 (see e.g.,FIGS. 15 and 18). In other implementations, the peak portion of a voidcell 104 can be less rounded or segmented as a result of a smallerradius or of a shallower depth of each outwardly curved surface, or bythe number of outwardly curved surfaces present in each void cell 104(see, for example, the less rounded and segmented peak portion of thevoid cells 104 with the smaller radius of outwardly curved surface andsmaller number of outwardly curved surfaces in FIGS. 4, 8 and 9). Asmaller radius may be approximately 1 mm. Cross sections of outwardlycurved surface in the walls of a void cell 104 may vary from a minimalindention, as minimally required to break the line running from thetangent from one corner of the void cell 104 to the next corner of thevoid cell 104, to as great as an ellipse, which extends into the voidcell 104 by half its width. Similarly, the opening or top (e.g., opening114) of the void cell 104 can vary in shape as a result of a smallerradius or of a shallower depth of each outwardly curved surface, or bythe number of outwardly curved surfaces present in each void cell 104.The opening or top of the void cell 104 can be open to atmosphere.

In other implementations, outwardly curved surfaces can be molded onlyin the peak portion, only in the base portion, or in both the peakportion and the base portion. Stiffness can be varied depending on themolding of these different patterns.

The cellular cushioning system 100 may be manufactured using a varietyof manufacturing processes (e.g., blow molding, thermoforming,extrusion, injection molding, laminating, etc.). For example, in oneimplementation, the cellular cushioning system 100 may be manufacturedvia single array sheet or roll-fed. In one implementation, the system100 is manufactured by forming two separate arrays, a first array 106and a second array 108. The two arrays are then laminated, glued, orotherwise attached together at the peak surfaces of the peak portion ofthe void cells in the first array 106 and the second array 108. Forexample, the peak surfaces of the peak portions of the void cells (e.g.,peak surface 112 of void cell 104) of the first array 106 are attachedto the peak surfaces (e.g., peak surface of void cell 102 (not shown))of the peak portions of the void cells 104 of the second array 108.

The void cells 104 are hollow chambers that resist deflection due tocompressive forces, similar to compression springs. At least thematerial, wall thickness, size, and shape of each of the void cells 104define the resistive force each of the void cells can apply. Materialsused for the void cells 104 are generally elastically deformable underexpected load conditions and will withstand numerous deformationswithout fracturing or suffering other breakdown impairing the functionof the cellular cushioning system 100. Example materials includethermoplastic urethane, thermoplastic elastomers, styrenic co-polymers,rubber, ethyl acetate, Dow Pellethane®, Lubrizol Estane®, Dupont™Hytrel®, ATOFINA Pebax®, and Krayton polymers. Further, the wallthickness may range from 5 mil to 160 mil. Still further, the size ofeach of the void cells may range from 5 mm to 70 mm sides in a cubicalimplementation. Further yet, the void cells may be cubical, pyramidal,hemispherical, or any other shape capable of having a hollow interiorvolume. Other shapes may have similar dimensions as the aforementionedcubical implementation. Still further, the void cells may be spaced avariety of distances from one another. An example spacing range is 2.5mm to 150 mm.

In one implementation, the void cells 104 have a square or rectangularbase shape, with a trapezoidal volume and a rounded top. That void cell104 geometry may provide a smooth compression profile of the system 100and minimal bunching of the individual void cells 104. Bunching occursparticularly on corners and vertical sidewalls of the void cells wherethe material buckles in such a way as to create multiple folds ofmaterial that can cause pressure points and a less uniform feel to thecellular cushioning system overall.

The material, wall thickness, cell size, and/or cell spacing of the voidcells 104 within the cellular cushioning system 100 may be optimized tominimize generation of mechanical noise by compression (e.g., bucklingof the sidewalls) of the void cells. For example, properties of the voidcells 104 may be optimized to provide a smooth relationship betweendisplacement and an applied force. Further, a light lubricating coating(e.g., talcum powder or oil) may be used on the exterior of the voidcells 104 to reduce or eliminate noise generated by void cellscontacting and moving relative to one another. Reduction or eliminationof mechanical noise may make use of the cellular cushioning system 100more pleasurable to the user.

Each void cell 104 can be surrounded by neighboring void cells within anarray. For example, void cell 102 is surrounded by three neighboringvoid cells 116 within the first array 106. In cellular cushioning system100, there are three neighboring void cells for each corner void cell,five neighboring void cells for each edge cell, and eight neighboringvoid cells for the center void cell. Other implementations may havegreater or fewer neighboring void cells for each void cell.

Further, in implementations where an array has an opposite array, eachvoid cell may have a corresponding opposing void cell within theopposite array. For example, void cell 102 in the first array 106 isopposed by void cell 104 in the second array 108. Other implementationsdo not include opposing void cells for some or all of the void cells.

The neighboring void cells and opposing void cells are collectivelyreferred to herein as adjacent void cells. In various implementations,one or more of the neighboring void cells, opposing void cells, andopposing neighbor void cells are not substantially compressed within anindependent compression range of an individual void cell.

In one implementation, the void cells are filled with ambient air. Inanother implementation, the void cells are filled with a foam or a fluidother than air. The foam or certain fluids may be used to insulate auser's body, facilitate heat transfer from the user's body to/from thecellular cushioning system 100, and/or affect the resistance todeflection of the cellular cushioning system 100. In a vacuum ornear-vacuum environment (e.g., outer space), the hollow chambers may beun-filled.

Further, the void cells may have one or more apertures or holes (notshown) through which air or other fluid may pass freely when the voidcells are compressed and de-compressed. By not relying on air pressurefor resistance to deflection, the void cells can achieve a relativelyconstant resistance force to deformation. Still further, the void cellsmay be open to one another (i.e., fluidly connected) via passages (notshown) through the array. The holes and/or passages may also be used tocirculate fluid for heating or cooling purposes. For example, the holesand/or passages may define a path through the cellular cushioning system100 in which a heating or cooling fluid enters the cellular cushioningsystem 100, follows a path through the cellular cushioning system 100,and exits the cellular cushioning system 100. The holes and/or passagesmay also control the rate at which air may enter, move within, and/orexit the cellular cushioning system 100. For example, for heavy loadsthat are applied quickly, the holes and/or passages may restrict howfast air may exit or move within the cellular cushioning system 100,thereby providing additional cushioning to the user.

The holes may be placed on mating surfaces of opposing void cells on thecellular cushioning system 100 to facilitate cleaning. Morespecifically, water and/or air could be forced through the holes in theopposing void cells to flush out contaminants. In an implementationwhere each of the void cells is connected via passages, water and/or aircould be introduced at one end of the cellular cushioning system 100 andflushed laterally through the cellular cushioning system 100 to theopposite end to flush out contaminants. Further, the cellular cushioningsystem 100 could be treated with an anti-microbial substance or thecellular cushioning system 100 material itself may be anti-microbial.

FIG. 2A illustrates a top view of an example base portion of a void cell200 in one array of the example cellular cushioning system. The baseportion of the void cell 200 is cube-shaped with four sidewalls 220. Thefour sidewalls 220 each have one outwardly curved surface (outwardlycurved surface 210) and two inwardly curved surfaces (inwardly curvedsurfaces 226). The outwardly curved surfaces 210 have curvatures thatface away from the interior of the void cell 200. The inwardly curvedsurfaces 226 have curvatures that face toward the interior of the voidcell 200.

A circle 222 can be projected from each outwardly curved surface 210,each outwardly curved surface 210 having a characteristic radius 228 anda characteristic depth 224. Radius and depth of each outwardly curvedsurface may vary from the characteristic radius and depth (e.g. vary 20%or less, or less than both half a length and half a width of therectangular overall outline). The size of the radii and the depths ofthe outwardly curved surface can vary in different implementations andin the same void cell. For instance, FIGS. 3, 5, and 7 show three voidcells with the same geometry except for outward facing radius ofdifferent magnitude. Each void cell has the same number of outwardfacing radii per side. By varying the magnitude of the radii in eachvoid cell, the structures deflect very differently, as shown in FIGS. 21and 22 in Configurations A, D, and C, respectively.

The elastic modulus or stiffness in the void cells can be manipulated byvarying the number, the depths, and the locations (e.g., verticalheight) of the radii in the void cells. The outwardly curved surfacesprevent buckling and provide support for high impact by absorbingenergy.

FIG. 2B illustrates a top view of an example base portion of the voidcell 200 in one array of the example cellular cushioning system. Thevoid cell 200 is cube-shaped with four sidewalls 220 (as depicted with arectangular overall outline 204 of the base portion of the void cell).The four sidewalls 220 each have one outwardly curved surface (outwardlycurved surface 210) and two inwardly curved surfaces (inwardly curvedsurfaces 226). The outwardly curved surfaces 210 have curvatures thatface away from the interior of the void cell 200. The inwardly curvedsurfaces 226 have curvatures that face toward the interior of the voidcell 200.

The outwardly curved surfaces 210 dominate the overall design of thevoid cell 200. Specifically, the outwardly curved surfaces 210constitute a substantial portion of the overall exterior surface area ofeach void cell 200. Specifically, the outwardly curved surfaces 210substantially exceed a portion of the overall perimeter 202 (defined asgreater than 25% of the overall perimeter 202 and depicted in a boldline) of the void cell 200. The perimeter 202 length substantiallyexceeds an overall outline 204 length of a base portion (not shown) ofeach molded void cell. The inwardly curved surfaces 226 substantiallyrecess a portion of the overall perimeter (defined as less than 25% ofthe overall perimeter 202 and depicted in a dashed line) of the voidcell 200.

FIG. 3 illustrates a top view of the example cellular cushioning systemin FIG. 1. As shown, the cellular cushioning system 300 includes voidcells (e.g., void cell 302) arranged in a first array 306 and a secondarray 308 (not shown). FIG. 3 shows the first array 306 has void cells(e.g., void cell 302), which comprise of four outwardly curved surfaces(e.g., outwardly curved surface 310) in each sidewall 320 of each voidcell in the first array 306 in the cellular cushioning system 300.

FIG. 4 illustrates a perspective view of an example cellular cushioningsystem 400 in an unloaded state. The cellular cushioning system 400includes void cells (e.g., void cell 402 or void cell 404) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

The first array 406 and the second array 408 have void cells (e.g., voidcell 404), which comprise of four outwardly curved surfaces (e.g.,outwardly curved surface 410) in each sidewall (e.g., sidewall 420) ofeach void cell (e.g., void cell 404) in the first array 406 and thesecond array 408 in the cellular cushioning system 400. Each void cell(e.g., void cell 404) also comprise of four inwardly curved surfaces(e.g., inwardly curved surface 426), located on the corners of each voidcell.

FIG. 5 illustrates a top view of the example cellular cushioning systemin FIG. 4. As shown, the cellular cushioning system 500 includes voidcells (e.g., void cell 502) arranged in a first array 506 and a secondarray 508 (not shown). FIG. 5 shows the first array 506 has void cells(e.g., void cell 502), which comprise of four outwardly curved surfaces(e.g., outwardly curved surface 510) in each sidewall 520 of each voidcell in the first array 506 in the cellular cushioning system 500.

FIG. 6 illustrates a perspective view of an example cellular cushioningsystem 600 in an unloaded state. The cellular cushioning system 600includes void cells (e.g., void cell 602 or void cell 604) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

The first array 606 and the second array 608 have void cells (e.g., voidcell 604), which comprise of four outwardly curved surfaces (e.g.,outwardly curved surface 610) in each sidewall (e.g., sidewall 620) ofeach void cell (e.g., void cell 604) in the first array 606 and thesecond array 608 in the cellular cushioning system 600. Each void cell(e.g., void cell 604) also comprise of four inwardly curved surfaces(e.g., outwardly curved surface 626), wherein two inwardly curvedsurfaces are each sidewall (e.g., sidewall 620) of each void cell.

FIG. 7 illustrates a top view of the example cellular cushioning systemin FIG. 6. As shown, the cellular cushioning system 700 includes voidcells (e.g., void cell 702) arranged in a first array 706 and a secondarray 708 (not shown). FIG. 7 shows the first array 706 has void cells(e.g., void cell 702), which comprise of four outwardly curved surfaces(e.g., outwardly curved surface 710) in each sidewall 720 of each voidcell in the first array 706 in the cellular cushioning system 700.

FIG. 8 illustrates a perspective view of an example cellular cushioningsystem 800 in an unloaded state. The cellular cushioning system 800includes void cells (e.g., void cell 802 or void cell 804) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

The first array 806 and the second array 808 have void cells (e.g., voidcell 804), which comprise of four outwardly curved surfaces (e.g.,outwardly curved surface 810) in each sidewall (e.g., sidewall 820) ofeach void cell (e.g., void cell 804) in the first array 806 and thesecond array 808 in the cellular cushioning system 800. Each void cell(e.g., void cell 804) also comprise of four inwardly curved surfaces(e.g., inwardly curved surface 826), wherein two inwardly curvedsurfaces are each sidewall (e.g., sidewall 820) of each void cell.

FIG. 9 illustrates a top view of the example cellular cushioning systemin FIG. 8. As shown, the cellular cushioning system 900 includes voidcells (e.g., void cell 902) arranged in a first array 906 and a secondarray 908 (not shown). FIG. 9 shows the first array 906 has void cells(e.g., void cell 902), which comprise of four outwardly curved surfaces(e.g., curvature 910) in each sidewall 920 of each void cell in thefirst array 906 in the cellular cushioning system 900.

FIG. 10 illustrates a perspective view of an example cellular cushioningsystem 1000 in an unloaded state. The cellular cushioning system 1000includes void cells (e.g., void cell 1002 or void cell 1004) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

The first array 1006 and the second array 1008 have void cells (e.g.,void cell 1004), which comprise of two outwardly curved surfaces (e.g.,curvature 1010) on two opposing sidewalls (e.g., sidewall 1020) of eachvoid cell (e.g., void cell 1004) in the first array 1006 and the secondarray 1008 in the cellular cushioning system 1000. Each void cell (e.g.,void cell 1004) also comprise of four inwardly curved surfaces (e.g.,curvature 1026), where the two inwardly curved surfaces are on twoopposing each sidewall (e.g., sidewall 1020) of each void cell.

FIG. 11 illustrates a top view of the example cellular cushioning systemin FIG. 10. As shown, the cellular cushioning system 1100 includes voidcells (e.g., void cell 1102) arranged in a first array 1106 and a secondarray 1108 (not shown). FIG. 11 shows the first array 1106 has voidcells (e.g., void cell 1102), which comprise of four outwardly curvedsurfaces (e.g., curvature 1110) in each sidewall 1120 of each void cellin the first array 1106 in the cellular cushioning system 1100.

FIG. 12 illustrates a perspective view of an example cellular cushioningsystem 1200 in an unloaded state. The cellular cushioning system 1200includes void cells (e.g., void cell 1202 or void cell 1204) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

The first array 1206 and the second array 1208 have void cells (e.g.,void cell 1204), which comprise of four outwardly curved surfaces (e.g.,curvature 1210) in each sidewall (e.g., sidewall 1220) of a peak portion1232 of each void cell (e.g., void cell 1204) in the first array 1206and the second array 1208 in the cellular cushioning system 1200. Thesidewalls 1220 in the peak portions 1232 of each void cell (e.g., voidcell 1204) also comprise of four inwardly curved surfaces (e.g.,inwardly curved surfaces 1226). A base portion 1230 of each void cell1204 includes only the inwardly curved surfaces 1226.

FIG. 13 illustrates an elevation view of the example cellular cushioningsystem in FIG. 1. The cellular cushioning system 1300 includes voidcells (e.g., void cell 1302 or void cell 1304) arranged in a first array1306 and a second array 1308.

The first array 1306 and the second array 1308 have void cells (e.g.,void cell 1304), which comprise of four outwardly curved surfaces (e.g.,curvature 1310) in each sidewall (e.g., sidewall 1320) of a peak portion1332 of each void cell (e.g., void cell 1304) in the first array 1306and the second array 1308 in the cellular cushioning system 1300. Thesidewalls 1320 in the peak portions 1332 of each void cell (e.g., voidcell 1304) also comprise of four inwardly curved surfaces (e.g.,inwardly curved surfaces 1326). A base portion 1330 of each void cell1304 includes only the inwardly curved surfaces 1326.

FIG. 14 illustrates a top view of the example cellular cushioning systemin FIG. 12. As shown, the cellular cushioning system 1400 includes voidcells (e.g., void cell 1402) arranged in a first array 1406 and a secondarray (not shown). FIG. 14 shows the first array 1406 has void cells(e.g., void cell 1402), which comprise of four outwardly curved surfaces(e.g., curvature 1410) in each sidewall 1420 of each void cell in thefirst array 1406 in the cellular cushioning system 1400.

FIG. 15 illustrates a perspective view of an example cellular cushioningsystem 1500 in an unloaded state. The cellular cushioning system 1500includes void cells (e.g., void cell 1502 or void cell 1504) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells.

In FIG. 15, the first array 1506 and the second array 1508 have voidcells (e.g., void cell 1504), which comprise of four outwardly curvedsurfaces (e.g., curvature 1510) in each sidewall (e.g., sidewall 1520)of a peak portion 1532 of each void cell (e.g., void cell 1504) in thefirst array 1506 and the second array 1508 in the cellular cushioningsystem 1500. The sidewalls 1520 in the peak portions 1532 of each voidcell (e.g., void cell 1504) also comprise of four inwardly curvedsurfaces (e.g., inwardly curved surfaces 1526). A base portion 1530 ofeach void cell 1504 includes only the inwardly curved surfaces 1526.

FIG. 16 illustrates an elevation view of the example cellular cushioningsystem in FIG. 1. The cellular cushioning system 1600 includes voidcells (e.g., void cell 1602 or void cell 1604) arranged in a first array1606 and a second array 1608.

The first array 1606 and the second array 1608 have void cells (e.g.,void cell 1604), which comprise of four outwardly curved surfaces (e.g.,curvature 1610) in each sidewall (e.g., sidewall 1620) of a peak portion1632 of each void cell (e.g., void cell 1604) in the first array 1606and the second array 1608 in the cellular cushioning system 1600. Thesidewalls 1620 in the peak portions 1632 of each void cell (e.g., voidcell 1604) also comprise of four inwardly curved surfaces (e.g.,inwardly curved surfaces 1626). A base portion 1630 of each void cell1604 includes only the inwardly curved surfaces 1626.

FIG. 17 illustrates a top view of the example cellular cushioning systemin FIG. 15. As shown, the cellular cushioning system 1700 includes voidcells (e.g., void cell 1702) arranged in a first array 1706 and a secondarray (not shown). FIG. 17 shows the first array 1706 has void cells(e.g., void cell 1702), which comprise of four outwardly curved surfaces(e.g., curvature 1710) in each sidewall 1720 of each void cell in thefirst array 1706 in the cellular cushioning system 1700.

FIG. 18 illustrates a perspective view of an example cellular cushioningsystem 1800 in an unloaded state. The cellular cushioning system 1800includes void cells (e.g., void cell 1802 or void cell 1804) arranged intwo arrays. In other implementations, there can be one or more than twoarrays of void cells. The arrays can be flat or curved.

The first array 1806 and the second array 1808 have void cells (e.g.,void cell 1804), which comprise of four outwardly curved surfaces (e.g.,curvature 1810) in each sidewall (e.g., sidewall 1820) of a peak portion1832 of each void cell (e.g., void cell 1804) in the first array 1806and the second array 1808 in the cellular cushioning system 1800. Thesidewalls 1820 in the peak portions 1832 of each void cell (e.g., voidcell 1804) also comprise of four inwardly curved surfaces (e.g.,inwardly curved surfaces 1826). A base portion 1830 of each void cell1804 includes only the inwardly curved surfaces 1826.

An array can include significant ribs (e.g., rib 1830) that separate thevoid cells (e.g., void cells 1804 and 1816). The ribs 1830 can belocated in the first array 1806 and/or or the second array 1808, andlocated in a variety of configurations between the void cells. Forexample, the ribs 1830, 1930, and 2030 in FIGS. 18-20 are located onlybetween the exterior void cells in the first array 1806 and the secondarray 1808. In another implementation the ribs 1830 may be locatedbetween all the void cells or only between certain selected void cells,such as between the void cells on the corners of an array. The number ofvoid cells and the number of ribs can vary depending on theimplementation. The positioning of the ribs in relation to the voidcells can vary. In some implementations, the ribs can be a thinstructure attached to a small contact point on the void cells, or theribs may be a wider structure that is attached to a larger contact pointon the void cells. The ribs can be located at the top or the bottom ofthe void cells. The ribs can be located near the end of the void cells,for example, close to the exterior of the array, or close to theinterior of the void cells. Or, in another implementation, the ribs canbe located near the center of the void cells.

The ribs provide a stiffening function to the array during compression.The material, wall thickness, cell size, and/or cell spacing of thecells within the cellular cushioning system 1800 may be optimized tominimize generation of mechanical noise by compression (e.g., bucklingof the sidewalls) of the void cells. For example, properties of thecells may be optimized to provide a smooth relationship betweendisplacement and an applied force. Further, a light lubricating coating(e.g., talcum powder or oil) may be used on the exterior of the voidcells to reduce or eliminate noise generated by void cells contactingand moving relative to one another. Reduction or elimination ofmechanical noise may make use of the cellular cushioning system 1800more pleasurable to the user.

FIG. 19 illustrates an elevation view of the example cellular cushioningsystem in FIG. 1. The cellular cushioning system 1900 includes voidcells (e.g., void cell 1902 or void cell 1904) arranged in a first array1906 and a second array 1908.

The first array 1906 and the second array 1908 have void cells (e.g.,void cell 1904), which comprise of four outwardly curved surfaces (e.g.,curvature 1910) in each sidewall (e.g., sidewall 1920) of a peak portion1932 of each void cell (e.g., void cell 1904) in the first array 1906and the second array 1908 in the cellular cushioning system 1900. Thesidewalls 1920 in the peak portions 1932 of each void cell (e.g., voidcell 1904) also comprise of four inwardly curved surfaces (e.g.,inwardly curved surfaces 1926). A base portion 1930 of each void cell1904 includes only the inwardly curved surfaces 1926.

The first array 1906 and the second array 1908 include significant ribs(e.g., rib 1930) that separate the void cells and provide stiffening tothe matrices during compression. The ribs 1930 can be located in thefirst array 1906 and/or or the second array 1908, and located in avariety of configurations between the void cells. For example, the ribs1830, 1930, and 2030 in FIGS. 18-20 are located only between theexterior void cells in the first array 1906 and the second array 1908.In another implementation the ribs 1930 may be located between all thevoid cells or only between certain selected void cells, such as betweenthe void cells on the corners of an array. The number of void cells andthe number of ribs can vary depending on the implementation. Thepositioning of the ribs in relation to the void cells can vary. In someimplementations, the ribs can be a thin structure attached to a smallcontact point on the void cells, or the ribs may be a wider structurethat is attached to a larger contact point on the void cells. The ribscan be located at the top or the bottom of the void cells. The ribs canbe located near the end of the void cells, for example, close to theexterior of the array, or close to the interior of the void cells. Or,in another implementation, the ribs can be located near the center ofthe void cells.

Different numbers and patterns of outwardly curved surfaces (e.g.,curvature 1910) can be molded into the void cells (e.g., void cell 1904)in an array. In some implementations, a cubic shape of a void cell(e.g., void cell 1902) may adopt the slope of its cubic shape of anadjacent or adjoined void cell (e.g., void cell 1904). In the cellularcushioning system 1900, the peak portion (e.g., peak portion 1912) ofthe void cell (e.g., void cell 1904) can be significantly rounded orsegmented as a result of a larger radius or of a deeper depth of eachcurvature (e.g., curvature 1910), or by the number of curvatures presentin each void cell. A larger radius may be approximately 20 mm. Inanother example, a larger radius may be half the length of the void cellless 1 mm. (The radii and depths of the curvatures are described indetail in FIG. 2.)

In other implementations, the peak portion of a void cell can be lessrounded or segmented as a result of a smaller radius or of a shallowerdepth of each curvature, or by the number of curvatures present in eachvoid cell (see, for example, the less rounded and segmented peak portionof the void cells with the smaller radius of curvatures and smallernumber of curvatures in FIGS. 4, 8 and 9). A smaller radius may beapproximately 1 mm. In FIG. 19, the peak portions are dome-shaped, andin a loaded condition the peak portions compress.

FIG. 20 illustrates a top view of the example cellular cushioning systemin FIG. 1. As shown, the cellular cushioning system 2000 includes voidcells (e.g., void cell 2002) arranged in a first array 2006 and a secondarray 2008 (not shown). The first array 2006 has void cells (e.g., voidcell 2002), which comprise of four outwardly curved surfaces (e.g.,curvature 2010) located in each sidewall 2020 of each void cell in thefirst array 2006 in the cellular cushioning system 2000.

The first array 2006 and the second array 2008 include significant ribs(e.g., rib 2030) that separate the void cells and provide stiffening tothe matrices during compression. The ribs 2030 can be located in thefirst array 2006 and/or or the second array 2008, and located in avariety of configurations between the void cells. For example, the ribs1830, 1930, and 2030 in FIGS. 18-20 are located only between theexterior void cells in the first array 2006 and the second array 2008.In another implementation the ribs 2030 may be located between all thevoid cells or only between certain selected void cells, such as betweenthe void cells on the corners of an array. The number of void cells andthe number of ribs can vary depending on the implementation. Thepositioning of the ribs in relation to the void cells can vary. In someimplementations, the ribs can be a thin structure attached to a smallcontact point on the void cells, or the ribs may be a wider structurethat is attached to a larger contact point on the void cells. The ribscan be located at the top or the bottom of the void cells. The ribs canbe located near the end of the void cells, for example, close to theexterior of the array, or close to the interior of the void cells. Or,in another implementation, the ribs can be located near the center ofthe void cells.

Different numbers and patterns of outwardly curved surfaces (e.g.,curvature 2010) can be molded into the void cells (e.g., void cell 2002)in an array. In some implementations, a cubic shape of a void cell(e.g., void cell 2002) may adopt the slope of its cubic shape of anadjacent or adjoined void cell (not shown). In the cellular cushioningsystem 2000, the peak portion (e.g., peak portion 2012) of the void cell(e.g., void cell 2002) can be significantly rounded or segmented as aresult of a larger radius or of a deeper depth of each curvature (e.g.,curvature 2010), or by the number of curvatures present in each voidcell. A larger radius may be approximately 20 mm. In another example, alarger radius may be half the length of the void cell less 1 mm. (TheRadii and depths of the curvatures are described in detail in FIG. 2.)

In other implementations, the peak portion of a void cell can be lessrounded or segmented as a result of a smaller radius or of a shallowerdepth of each curvature, or by the number of curvatures present in eachvoid cell (see, for example, the less rounded and segmented peak portionof the void cells with the smaller radius of curvatures and smallernumber of curvatures in FIGS. 4, 8 and 9). A smaller radius may beapproximately 1 mm. In FIG. 20, the peak portions are dome-shaped, andin a loaded condition the peak portions compress.

FIG. 21 shows a graph 2100 of force displacement of void cells in anarray of the described cushioning system. The lines on the graph showforce displacement curves based on Displacement (mm)×Load (N). The “TwinSquares” line correlates to an array of void cells with no outwardlycurved surfaces. The lines A-G correlate to the void cells in the arraysas follows:

Line A correlates to FIGS. 1 and 3

Line B correlates to FIGS. 4 and 5

Line C correlates to FIGS. 6 and 7

Line D correlates to FIGS. 8 and 9

Line E correlates to FIGS. 10 and 11

Line F correlates to FIGS. 12, 13, and 14

Line G correlates to FIGS. 15, 16, and 17

As shown in the graph, it takes a different amount of force to obtainthe same amount of displacement depending on the presences andconfiguration of outwardly curved surfaces in the sides of the voidcells. For example, lines B and D, which both represent configurationscomprising four outwardly curved surfaces in the sides of each void cellalmost trace each other in force displacement, and then diverge between11 and 12 mm displacement. As Radii are introduced into the void cells,splits are visible on the graph of two lines, which were almost thesame. Line C shows a configuration with an easy compression, then showsa higher elastic modulus as displacement increases. Line B has the sameslope as line C but progresses to show the higher elastic modulus of thevoid cells of the configuration represented. Compared to that, line Ghas relatively even compression (similar to foam), and then stiffens up.Forming the Radii in the curvatures of the void cell results in a 40%reduction of impact and compression.

FIG. 22 shows a table 2200 of load force based on 10%, 25%, 50%, and 75%compression for the void cells in arrays of the described cushioningsystems. The “TS” (twin squares) configuration data correlates to anarray of void cells with no outwardly curved surfaces. Theconfigurations A-G correlate to the void cells in the arrays as follows:

Configuration A correlates to FIGS. 1 and 3

Configuration B correlates to FIGS. 4 and 5

Configuration C correlates to FIGS. 6 and 7

Configuration D correlates to FIGS. 8 and 9

Configuration E correlates to FIGS. 10 and 11

Configuration F correlates to FIGS. 12, 13, and 14

Configuration G correlates to FIGS. 15, 16, and 17

The data in the table 2200 shows an increase in load force (N) resultsin greater measurements of compression. For example, a load force of1214 N for Configuration G, results in 75% compression, whereas a loadforce of only 376 N results in only 10% compression for Configuration G.

The array configuration with only two outwardly curved surfaces in eachvoid cell (Configuration E) requires a lower load force N (see loadforce of 1168N for 75% compression) as compared to configurations withfour outwardly curved surfaces in each void cell (Configurations A-D andF-G), which require load forces of 1214N and above for 75% compression.The array configuration with no outwardly curved surfaces in each voidcell (Configuration TS) requires an even lower load force N of 855N for75% compression as compared to the configuration with two outwardlycurved surfaces in each void cell (Configuration E).

Photographs of the void cells measured and depicted in the graph shownin FIG. 21 and the table in FIG. 22 are attached in an Appendix. TheAppendix includes photographs for Configurations TS and A-G (describedin FIGS. 21 and 22) at 10% compression, 25% compression, 50%compression, 75% compression, a side unloaded view, a side view, and atop view.

FIG. 23 illustrates example operations 2300 for manufacturing a cellularcushioning system. The cellular cushioning system may be molded, or inother implementations manufactured using a variety of manufacturingprocesses (e.g., blow molding, thermoforming, extrusion, injectionmolding, laminating, etc.). The cushioning system can comprise of one ormore arrays of void cells. The arrays can be flat (planar) or curved(non-planar).

A first molding operation 2302 molds a first array of void cells. Thevoid cells in the first array include both outwardly curved surfaces andinwardly curved surfaces. Each curvature of the outwardly curvedsurfaces can be configured in a sidewall of a void cell. Each curvatureof the inwardly curved surfaces can be configured on a corner of a voidcell. However, in other implementations, the outwardly curved surfacescan be configured on a corner of a void cell and the inwardly curvedsurfaces can be configured in a sidewall of a void cell. Otherconfigurations are contemplated. The outwardly curved surfacesconstitute a substantial portion of the overall exterior surface area ofeach void cell.

A second molding operation 2304 molds a second array of void cells. Thevoid cells in the first array include both outwardly curved surfaces andinwardly curved surfaces. Each curvature of the outwardly curvedsurfaces can be configured in a sidewall of a void cell. Each curvatureof the inwardly curved surfaces can be configured on a corner of a voidcell. The outwardly curved surfaces constitute a substantial portion ofthe overall exterior surface area of each void cell.

The void cells are hollow chambers that resist deflection due tocompressive forces, similar to compression springs. At least thematerial, wall thickness, size, and shape of each of the void cellsdefine the resistive force each of the void cells can apply. Materialsused for the void cells are generally elastically deformable underexpected load conditions and will withstand numerous deformationswithout fracturing or suffering other breakdown impairing the functionof the cellular cushioning system. Example materials includethermoplastic urethane, thermoplastic elastomers, styrenic co-polymers,rubber, ethyl acetate, Dow Pellethane®, Lubrizol Estane®, Dupont™Hytrel®, ATOFINA Pebax®, and Krayton polymers. Further, the wallthickness may range from 5 mil to 80 mil. Still further, the size ofeach of the void cells may range from 5 mm to 70 mm sides in a cubicalimplementation. Further yet, the void cells may be cubical, pyramidal,hemispherical, or any other shape with external facing curvature capableof having a hollow interior volume. Other shapes may have similardimensions as the aforementioned cubical implementation. Still further,the void cells may be spaced a variety of distances from one another. Anexample spacing range is 2.5 mm to 150 mm.

In one implementation, the base portion of the void cells can be squareor rectangular, with a trapezoidal volume and a rounded top. That voidcell geometry may provide a smooth compression profile of the system andminimal bunching of the individual void cells. Bunching occursparticularly on corners and vertical sidewalls of the void cells wherethe material buckles in such a way as to create multiple folds ofmaterial that can cause pressure points and a less uniform feel to thecellular cushioning system overall.

An attaching operation 2306 attaches the first array of void cells andthe second array of void cells together. The first array of void cellsand the second array of void cells can be laminated, glued, or otherwiseattached together at the peak surfaces of the peak portion of the voidcells in the first array and the second array. Due to varyingconfigurations with a different number of void cells in the two arrays,the attachment of the void cells to each other may occur at differentpoints of contact on each void cell.

The above specification, examples, and data provide a completedescription of the structure and use of exemplary embodiments of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended. Furthermore, structuralfeatures of the different embodiments may be combined in yet otherembodiments without departing from the recited claims.

What is claimed is:
 1. An energy absorbing, elastically deformable voidcell comprising: four sidewalls forming a rectangular outline, thesidewalls including: a base portion that includes only uninterruptedinwardly curved surfaces; and a peak portion that includes only oneuninterrupted outwardly curved surface on at least two of the sidewallsand uninterrupted inwardly curved surfaces on all of the sidewalls,wherein the outwardly curved surfaces constitute at least 20% of theoverall exterior surface area of the void cell, wherein the void cell iselastically deformable over at least 10% of its stroke, wherein the voidcell is open to atmosphere.
 2. The energy absorbing, elasticallydeformable void cell of claim 1, wherein a perimeter lengthsubstantially exceeds an overall outline length of a base portion of thevoid cell.
 3. The energy absorbing, elastically deformable void cell ofclaim 1, wherein an outwardly curved surface depth substantiallyrecesses from an overall outline of a base portion of the void cell. 4.The energy absorbing, elastically deformable void cell of claim 1,wherein the void cell includes a dome-shaped peak surface.
 5. The energyabsorbing, elastically deformable void cell of claim 1, wherein radii ofthe outwardly curved surfaces are less than both half a length and halfa width of the rectangular outline.